Inferior Alveolar Nerve Deficit Research Articles

Outcomes of Coronectomy and Total Odontectomy of Impacted Mandibular Third Molars

ObjectiveThe aim of this research was to evaluate the surgical complications and neurosensory deficits after coronectomy and the complete removal of mandibular third molars. MethodsThe study sample included patients requiring surgical removal of mandibular third molars. A coronectomy was conducted on 220 teeth showing signs of close proximity to the inferior alveolar canal. A complete extraction was performed on 218 teeth with no risk signs. The patients were evaluated at 1 week and 1, 3, 6, 12, and 24 months after surgery for pain, swelling, neurologic deficit, dry socket, postoperative bleeding, infection, root migration, and eruption. ResultsNo significant difference was noted in pain and swelling; however, bleeding and dry socket were significantly higher in the odontectomy group (P = .017). The inferior alveolar nerve deficit was higher in the odontectomy group (3.7%) than the coronectomy group (0.5%) (P = .017). The percentage and distance of root migration of coronectomised teeth at 3, 6, and 12 months were 60% (2.37 ± 0.96 mm), 66% (3.35 ± 0.86 mm), and 74% (3.85 ± 0.93 mm), respectively. ConclusionsCoronectomy is a safe procedure and should be performed when the roots are closely associated with the mandibular canal. Although root migration is common, the likelihood of root exposure is low and roots rarely need removal.

Incidence neurosensory deficit in mandibular fractures.

Sensory disturbances in the inferior alveolar nerve (IAN) prior to treatment can be attributed to various factors, including the site, type of fracture, and fracture displacement. Therefore, it is of interest to assess the incidence of inferior alveolar nerve injuries associated with mandibular fractures before and after surgical treatment. Group A consisted of patients with inferior alveolar nerve paresthesia before treatment, while Group B consisted of patients with inferior alveolar nerve paresthesia after treatment. A significant difference was observed between the two groups, with a p-value of 0.031 (p <0.05) with the overall incidence of IAN deficit was 57.33% before treatment and 61.33% after treatment. These findings highlight the importance of promptly identifying and managing IAN injuries to minimize long-term consequences.

Neurosensory deficit of inferior alveolar nerve after bilateral sagittal split osteotomy, advancement versus setback: An observational study

Aim: The aim of this study was to compare the incidence of inferior alveolar sensory deficits, its association with various intraoperative nerve encounter status and the possible outcome of neurosensory deficits (NSDs) of the bilateral sagittal split osteotomy (BSSO) advancement, and setback procedures. Materials and Methods: This was an observational study among the oral and maxillofacial surgeons of south India who had expertise in the field of orthognathic surgery. A self-administered questionnaire (SAQ) with closed-ended answers was prepared using Google Forms (Google Inc.), pretested, and was sent to the prospective participants selected by convenience sampling through various social media outlets. A total of 1600 participants were included, and the sample size was estimated by the formula = 4pq/d2 and assessed 800 cases each of BSSO setback and advancement surgeries. Since the study focused on the NSD of the inferior alveolar nerve (IAN) post-BSSO, the advancement procedures, setback procedures, and various nerve encounter statuses were considered the variables. All the study procedures were performed as per the ethical guidelines laid down by the Declaration of Helsinki (October 2013) after approval by the Institutions Human Ethics Committee (IHEC), Rajah Muthiah Medical College, Annamalai University. Results: Chi-squared test was used to assess the qualitative variables. The incidence of NSDs was 17.7% in the setback cases and with respect to advancement, the NSD was 15.1%, P < 0.08 indicating no statistically significant difference. When comparing the independent nerve encounter status and NSDs between the groups, the cases where the nerve got transected post osteotomy, necessitating repair as well as those needing dissection due to its presence in the proximal fragment presented with a higher incidence of NSDs which was clinically and statistically significant, P < 0.001. Conclusion: No significant difference was observed in the NSD after mandibular sagittal split advancement and setback procedures. The status of the IAN intraoperatively can influence the incidence of postoperative prolonged IAN NSDs.

The neurosensory deficit of inferior alveolar nerve following bilateral sagittal split osteotomy: a prospective study.

Investigation in Saudi Arabia or the Arab Gulf States to assess the unfavorable impacts of the bilateral sagittal split osteotomy (BSSO) is non-existent, so questions have been raised about the success rate of this operation and the frequency of unwilling outcome. To address these worries, we directed a case series study to evaluate the hypoesthesia, a type of neurosensory deficit (NSD) of the inferior alveolar nerve (IAN) after BSSO, and if the hypoesthesia outcome will improve if the surgeries performed by a single surgeon. This was a prospective case series study for the patient who underwent BSSO in a medical complex that is considered one of the largest in Saudi Arabia (Riyadh). The inclusion criteria include patient aged 18-40years, any gender, and American Society of Anesthesiologists (ASA) class I. They will undergo BSSO for either mandibular, retrognathia, prognathic, or to follow the maxilla. The outcome will be measured after evaluating the neurosensory by four means light touch (LT), pinprick (PP), 2-point discrimination (2PD), and thermal sensations (TT) in four repeated measurements (preoperatively, 1week, 1month, 3months postoperatively) as the primary outcome. Other confounding factors were the secondary outcome (age, gender, visualization of the I.A.N, the type of mandibular movement, split favorability, mandibular canal location, and patient reports about paresthesia or dysesthesia on any given side); these data analyses were carried out using SPSS ver. 25 data processing software. The nerve was visible in 93% of cases. During the operation, none of the nerves was transected. Hypoesthesia on the first follow-up was 94% of cases for LT, 92% for PP, 82% for TT, and 100% for the 2PD. On the last follow-up, the patients still had hypoesthesia for the LT 51%, PP 35%, TT41%, and 2PD 55%; age and sex did not significantly affect hypoesthesia outcomes. Nerve visibility and inferior alveolar nerve canal (IAC) distance did not influence the results. The level of confidence for all tests was set at p < 0.05. The 2PD sensation was the most affected sense on the last visit, and the right side of the chin and lower lip was affected most both on early and long-term follow-up due to several reasons. A 3-month period was enough as a recovery time to restore 100% of neurological sensation for 45% of the sample, which is similar to several studies in the literature. A single surgeon did not show superior result compared to two surgeons' literature papers. Advancement movement was associated with a high percentage of hypoesthesia.

INFERIOR ALVEOLAR NERVE DEFICIT AFTER REMOVAL OF LOWER THIRD MOLARS-FREQUENCY AND FACTORS AFFECTING NERVE DAMAGE IN PROSPECTIVE CLINICAL STUDY OF 1487 EXTRACTIONS IN 1185 PATIENTS

Objective:&#x0D; To determine the Frequency of inferior alveolar nerve injury and to assess the relationship of the nerve deficit with contributory risk factors like causes of removal, patient’s age, and anesthetic modality.&#x0D; Materials and Methods:&#x0D; All the procedures were carried out in Maroof International Hospital from January 2016 to August 2020. About 1185 consecutive patients were included in the study who were treated over a period of 5 years. A total of 1487 surgical extractions were performed. Surgery was done either under local anesthesia (72.1%) or IV sedation with local anesthesia (27.9%). All the procedures were performed by the same single senior consultant with the same two nurses. Follow up was done at one, three, and six weeks and six months.&#x0D; Results:&#x0D; Eight cases (0.53%) had temporary inferior alveolar nerve deficit which settled within six weeks. No permanent neurological damage was observed. Cases with pericoronitis were significantly associated with postoperative temporary nerve damage (p&lt;0.001). Age, gender, and anesthetic modality were not significantly related to nerve injury.&#x0D; Conclusion:&#x0D; Patients with preoperative pathology like pericoronitis have more chances of temporary nerve injury after removal. Preoperative counseling about possible nerve damage shall be done.

Surgical morbidities of sagittal split ramus osteotomy versus intraoral vertical ramus osteotomy for the correction of mandibular prognathism: a randomized clinical trial

The sagittal split ramus osteotomy (SSRO) and intraoral vertical ramus osteotomy (IVRO) are two common orthognathic procedures for the treatment of mandibular prognathism. This randomized clinical trial compared the surgical morbidities between SSRO and IVRO for patients with mandibular prognathism over the first 2 years postoperative. Ninety-eight patients (40 male, 58 female) with a mean age of 24.4±3.5 years underwent bilateral SSRO (98 sides) or IVRO (98 sides) as part or all of their orthognathic surgery. IVRO presented less short-term and long-term surgical morbidity in general. The SSRO group had a greater incidence of inferior alveolar nerve deficit at all follow-up time points (P< 0.01). There was more TMJ pain at 6 weeks (P= 0.047) and 3 months (P= 0.001) postoperative in the SSRO group. The SSRO group also presented more minor complications, which were related to titanium plate exposure and infection. There were no major complications for either technique in this study. Despite the need for intermaxillary fixation, IVRO appears to be associated with less surgical morbidity than SSRO when performed as a mandibular setback procedure to treat mandibular prognathism.

FREQUENCY OF INJURY TO LINGUAL NERVE &amp; INFERIOR ALVEOLAR NERVE IN CASE OF MANDIBULAR 3RD MOLAR IMPACTION

Objective: The main objective of the study is to determine the frequency of injury to lingual nerve &amp; inferior alveolar nerve in case of mandibular 3rd molar impaction. Materials and Methods: This cross sectional study was conducted in Bakhtawar Amin Dental Hospital, Multan, during July 2018 to December 2018 with the permission of ethical committee of hospital. A total of 100 mandibular extractions were performed with the age range from 15-80. 25 patients were males and 75 were females. The predictor variables for the study were age, gender, level of impaction(soft tissue, partial bony or total bony) ,type of buccal flap raised (in surgical extractions), lingual flap retraction and protection, surgeon’s experience (specialists, residents, house officers or students) and the tooth side (right or left) in relation to the handednessof the operator (R/L). The outcome variable was the presence of postoperative lingual neurosensory deficit and inferior alveolar nerve deficit. Results: Out of 100 patients, six patients were diagnosed with lingual nerve paraesthesia on 1st and 7th postoperative day evaluation. The overall incidence rate of lingual nerve injury was 6%. One patient with paraesthesia was lost from the study after approximately 3 months of observation due to geographical relocation but this patient had definite sign of return of sensation when he was lost from study. Conclusion: It is concluded that the risk of lingual nerve paraesthesia is higher than inferior alveolar nerve paraesthesia post operatively after third molar extractions.

Determining the risk relationship associated with inferior alveolar nerve injury following removal of mandibular third molar teeth: A systematic review

PurposeThis study analyzes the risk factors associated with the incidences of inferior alveolar nerve (IAN) injury after surgical removal of impacted mandibular third molar (IMTM) and to evaluate the contribution of these risk factors to postoperative neurosensory deficits. Materials and methodsAn exhaustive literature search has been carried out in the COCHRANE library and PubMed electronic databases from January 1990 to March 2019 supplemented by manual searching to identify the related studies. Twenty-three studies out of 693 articles from the initial search were finally included, which summed up a total of 26,427 patients (44,171 teeth). ResultsOur results have been compared with other current available papers in the literature review that obtained similar outcomes. Among 44,171 IMTM extractions performed by various grades of operators, 1.20% developed transient IAN deficit and 0.28% developed permanent IAN deficit respectively. Depth of impaction (P<0.001), contact between mandibular canal (MC) and IMTM (P<0.001), surgical technique (P<0.001), intra-operative nerve exposure (P<0.001), and surgeon's experience (P<0.001) were statistically significant as contributing risk factors of IAN deficits. ConclusionRadiographic findings, such as depth of impaction, proximity of the tooth to the mandibular canal, surgical technique, intra-operative nerve exposure, and surgeon's experience were high risk factors of IAN deficit after surgical removal of IMTMs.

Neurosensory Deficit of Inferior Alveolar Nerve Following Mandibular Orthognathic Surgery.

Neurosensory Deficit of Inferior Alveolar Nerve Following Mandibular Orthognathic Surgery.

Computer-Aided Design/Computer-Aided Manufacturing Cutting Guides for Odontectomy of Deeply Impacted Mandibular Third Molars.

AIM:To evaluate a new technique for surgical removal of deeply impacted mandibular third molars (DIMTM), using computer-guided cutting guide to maintain inferior alveolar nerve (IAN) integrity and the covering buccal bone.PATIENTS AND METHODS:Eighteen cases indicated for removal of DIMTM. Cone-beam Computed Tomography (CBCTs) used to determine the tooth’s relation to the IAN. Computer-guided software used for fabrication of surgical cutting guide stent to expose the impacted tooth and repositioning of bone after odontectomy without fixation. Clinical assessment included a neurosensory deficit of IAN, pain using a visual analogue scale (VAS), facial swelling, and maximal mouth opening (MMO). CBCTs were taken immediately and six months postoperatively to evaluate position and healing of bone.RESULTS:None of the patients showed a permanent neurological deficit of IAN while all patients showed normal parameters of pain, facial swelling and MMO.CONCLUSION:this technique has shown the accurate determination of the bony window cuts with subsequent preservation of IAN and external oblique ridge.

Maxillomandibular advancement for obstructive sleep apnea.

: We aimed to present our clinical experience with maxillomandibular advancement (MMA) for the treatment of obstructive sleep apnea (OSA) syndrome and to compare our results with literature data. : The patients who were operated for OSA in the last 10 years were included in the study. A detailed patient's charts review was retrospectively performed. Inclusion criteria were to be available with preoperative and postoperative polysomnography data. : There were totally 7 cases who underwent MMA procedure for OSA in our clinic. The mean age was 38.6 ± 8.1 years. Surgical success was achieved in all cases (100%). The mean preoperative and postoperative apnea-hypopnea indexes were 63.3 ± 35.2 and 7.5 ± 3.4, respectively (P < 0.05). The most common complication was inferior alveolar nerve deficit following bilateral sagittal split osteotomy. The facial numbness was temporary in 4 (57.1%), and permanent in one case (14.3%). Our surgical results in MMA is compatible with literature data. MMA is the choice of treatment in severe OSA in case of positive airway pressure therapy intolerance.

Thermography: A newer diagnostic assessment tool in dentistry

Thermology is the study and application of bio-thermal process to assess health or disease while thermography is a technique of measurement of skin temperature distribution on the body over a given period of time. It is a noncontact, noninvasive method that utilizes the heat from an object to detect, display, and record thermal patterns and temperature across the surface of the object and it employs images and visually evaluates the thermal changes. The principle of thermography is based on the amount of blood circulation at different layers of the skin, as it varies, the temperature also changes accordingly. Consequently, disorders that affect the blood flow too result in abnormalities in temperature distribution and these when evaluated will provide valid diagnostic information. Thermography is being used to detect various pathological conditions in the medical and dental field. Various orofacial conditions in which thermography can be used are chronic orofacial pain, temporomandibular joint disorders, quantification of thermal insult to pulp, assessing inferior alveolar nerve deficit, and detection of herpes labialis in prodromal phase. Here, we discuss with the history, basics, and various applications of thermography in dentistry.

Long-term morbidities of coronectomy on lower third molar

To monitor the long-term morbidity of retained roots up to 5 years following lower third molars coronectomy with close proximity to the inferior alveolar nerve (IAN). A prospective study on long-term morbidities after lower third molar coronectomy. This study included 612 lower third molar coronectomies in 458 patients. The prevalence of IAN injury was 0.16% (1/612) and was temporary. Long-term postoperative infection occurred in 1 case at 6 months following surgery and another at 12 months. No infection was found after 12 months. The incidence rates of pain at 6 months, 12 months, 24 months after surgery were 0.50% (3/596), 0.38% (2/529), 0.49% (2/411), respectively. Root exposure was noted in 2.3% of cases (14/612). Reoperation to remove the exposed root did not cause any IAN deficit. Lower third molar coronectomy is safe in the long term.

Thermography in Diagnosis of Disorders in Head and Neck Region

Thermology is the study and application of biothermal process to assess health or disease and the word thermography employs imaging and visual evaluation of those thermal changes. Three different types of thermography are Liquid crystal thermography, Digital Infrared thermography and Dynamic area telethermometry. In the recent times, thermography has shown its relevance in various aspects of dental and medical diagnosis. Its application in diagnosing the disorders of head and neck region includes, chronic orofacial pain patients, TMJ disorders, inferior alveolar nerve deficit, cranio mandibular disorders post surgical inflammation, myofacial symptoms and many others. Since thermography has proved to be useful in diagnosing a number of disorders in head and neck region, it becomes necessary to gain further knowledge about this emerging technique in the related field. The present review presents some of applications of the thermography in head and neck region.

Low to high oblique ramus piezoosteotomy: A pilot study

Two major drawbacks of classical bilateral sagittal split osteotomy (BSSO) are occasional inferior alveolar nerve damage and bad splits. In order to avoid these two well-known disadvantages and benefit from ultrasonic bone cutting, a low-to-high oblique piezoosteotomy (LHO) was developed from Schlössmann's 1922 high oblique osteotomy, clinically evaluated with a standard and a novel osteosynthesis system.Eighty-five patients were retrospectively evaluated, 23 with an LHO osteotomy with standard osteosynthesis, 33 LHO with a dedicated plate osteosynthesis and compared to 29 patients with BSSO and standard osteosyntheses.The mean mandibular advancement in the LHO standard osteosynthesis/LHO dedicated plate osteosynthesis/BSSO collectives was 4.7 ± 2.5/7.8 ± 7.1/4.1 ± 2.8 mm, the mean one year relapse 2.6 ± 0.8 (p = 0.58)/1.4 ± 1.4 (p = 0.28)/2.1 ± 1.4 mm; the mean mandibular setback was 6.9 ± 3.6/7.7 ± 4.1/8.1 ± 4.9 mm and the one year relapse 2.9 ± 2.9 (p = 0.16)/1.4 ± 1.0 (p = 0.38)/1.5 ± 1.9 mm; clockwise rotation of the mandible was 5.2 ± 3.2/6.3 ± 5.1/10.2 ± 6.9°, the one year relapse 2.7 ± 1.2 (p = 0.18)/2.1 ± 1.7 (p = 0.09)/11.4 ± 9.3°; counterclockwise rotation averaged 6.4 ± 3.2/6.5 ± 7.9/6.5 ± 6.1° with a mean one year relapse of 3.3 ± 0.6 (p = 0.37)/3.7 ± 1.9 (p = 0.21)/4.5 ± 6.2°.LHO had 3%, BSSO 5% three months postoperative inferior alveolar nerve deficit (p = 0.17). The operation time was significantly shorter when LHO and dedicated plates were used compared to BSSO. Two broken conventional plates occurred in LHO, which stimulated the development of the dedicated plates used, one in BSSO; four bad splits in BSSO and two in LHO. Reosteosyntheses were performed using the newly developed dedicated “orthognathics” plate.LHO was successfully performed, easier and faster than BSSO. Gonial angle modifications were possible due to the oblique cut. Postoperative stability appears sufficient for moderate repositioning with a lower incidence of bad split and inferior alveolar nerve irritation, moreover blood loss was reduced. Since 2 standard miniplate fractures occurred in LHO, the “orthognathics” osteosynthesis was developed, applied and no further osteosynthesis fractures were seen.

Trigeminal Neurosensory Deficit and Patient Reported Outcome Measures: The Effect on Quality of Life

ObjectivesTo investigate the effect of persistent neurosensory disturbance of the lingual nerve (LN) or inferior alveolar nerve (IAN) on general health and oral health- related quality of life (QoL).MethodsThe study design was a case-control study. Patients with persistent neurosensory deficit of LN or IAN after lower third molar surgery (for 12 months or more) were the study group. The control group was an age and gender matched sample of patients who had dental extractions or lower third molar surgeries without trigeminal neurosensory deficit. The outcome variables were the general health and oral health-related QoL. General health-related QoL was assessed using the 36-item Short Form Health Survey (SF-36) and oral health-related QoL using the 14-item Short Form Oral Health Impact Profile (OHIP-14). Differences in SF-36 scores and OHIP-14 scores between the groups were compared.ResultsForty-eight subjects (24 cases and 24 controls) were recruited. When compared to the control group, patients with neurosensory deficits had poorer Mental-Health Component Scores (MCS) (p = 0.005), General Health (p = 0.023), Vitality (p = 0.048), Social Functioning (p = 0.003), Role-emotion (p = 0.008) and Mental Health (p = 0.022). The OHIP-14 scores were also significantly worse in this patients with neurosensory deficits compared with the control group (p = 0.002). When compared within the study group, older patient with neurosensory deficit was found to correlate with worse Physical Health Component Scores (PCS) (p = 0.02) and OHIP-14 scores (p = 0.02), while more severe visualized analog scaling rating of numbness was correlated with a worse PCS (p = 0.034).ConclusionsPatients with persistent LN or IAN deficit after lower third molar surgery have poorer health-related QoL and poorer oral health-related QoL than those without such deficits.

Trigeminal Neurosensory Deficit and Patient Reported Outcome Measures: The Effect on Life Satisfaction and Depression Symptoms

ObjectivesTo investigate the effect of persistent neurosensory disturbance of the lingual nerve (LN) or inferior alveolar nerve (IAN) on life satisfaction and depression symptoms.MethodsThis study recruited patients with persistent LN or IAN deficit as a consequence of lower third molar surgery for 12 months or more to form the study group. A control group was formed by matching age and gender of recruited subjects in the study group with patients without the neurosensory complications. Life satisfaction was assessed with Satisfaction With Life Scale (SWLS) and depression symptoms were assessed with 20-item Center for Epidemiological Studies Depression scale (CESD-20).ResultsFourty-eight participants (24 cases and 24 controls) were recruited. Patients with LN or IAN deficits after lower third molar surgery were less satisfied with their lives when compared to the control group (p<0.001). They were presenting with more depression symptoms (p = 0.001). 45.8% of the study group subjects had a CESD-20 score of 16 or above. Older patients presented with more depression symptoms among the subjects with neurosensory disturbance after lower third molar surgery (p = 0.02).ConclusionsIndividuals with permanent trigeminal neurosensory deficit after lower third molar surgery have worse life satisfaction and more depressive symptoms when compared to those who did not suffer from the surgical complication.

Coronectomy of the Lower Third Molar Is Safe Within the First 3 Years

There is no long-term evaluation on the safety of coronectomy of the lower third molar. The aim of this study was to investigate the 3-year morbidity of coronectomy of the lower third molars and to monitor the behavior and migration pattern of the retained roots after coronectomy. This was a prospective cohort study. Patients with lower third molars with specific radiographic sign(s) showing proximity of the roots to the inferior alveolar nerve who underwent coronectomy in a previous randomized clinical trial were reviewed postoperatively in the first week and the third, sixth, 12th, 24th, and 36th months. The morbidities of infection, pain, root eruption, reoperation to remove the root, and the development of any pathology were recorded. The pattern of any root migration was analyzed. Ninety-eight patients (35 men and 63 women; mean age, 25.7 yrs; standard deviation, 7.9 yrs) with 135 coronectomies completed the 36-month review. None presented with infection or pain from the postoperative third month onward. Root eruption causing sensitivity occurred in 3% (4/135) of the sample and the erupted roots were removed. None of the reoperated cases presented with a postoperative inferior alveolar nerve deficit. No pathology developed in any of the retained roots after coronectomy. Root migration was noted in most cases in the first 12 months, and all roots stopped migrating from the 24th month onward. The mean root migration at 36 months was 2.8 mm (standard deviation, 1.4 mm). This study confirms that retained roots after coronectomy in the lower third molars produce no complications in terms of infection, pain, or the development of pathologies within the first 3 years. Root eruption can occur in a very small percentage of patients and may require reoperation to remove the root.

Treatment Modalities of Neurosensory Deficit After Lower Third Molar Surgery: A Systematic Review

To conduct a systematic review to answer the clinical question, "What are the available treatment modalities and their outcomes of neurosensory deficit after lower third molar surgery?" A systematic search, including a computer search of several databases with specific keywords, a reference search, and a manual search of 3 key maxillofacial journals were performed. Relevant articles were then evaluated and those that fulfilled the 6 predetermined criteria were chosen to enter the final review. The various treatment modalities and their outcomes of neurosensory deficit after lower third molar surgery, in the selected studies in the final review, were analyzed. Ten articles entered the final review. Six treatment modalities of lingual nerve or inferior alveolar nerve deficit after lower third molar surgery were identified. External neurolysis, direct suturing, autogenous vein graft, and a Gore-Tex tube as a conduit were the 4 surgical treatments. Significant improvement after surgical treatment ranged from 25% to 66.7%. Acupuncture and low-level laser therapy were 2 available nonsurgical treatment modalities that were found to have produced significant improvement in sensation after treatment in more than 50% of subjects. There was insufficient information to determine the best timing of treatment of nerve injury after third molar surgery. Four surgical treatments and 2 nonsurgical treatments were identified in the management of neurosensory disturbance after lower third molar surgery. Most treatments showed an improvement in sensation but the outcomes were variable. Complete recovery was uncommon in all kinds of available treatments.

Incidence of neurosensory deficits and recovery after lower third molar surgery: a prospective clinical study of 4338 cases

A prospective study of all lower third molar surgery performed in the outpatient extraction clinic of a teaching dental hospital was conducted from January 1998 through October 2005 to determine the incidence of subsequent neurosensory deficit due to inferior alveolar nerve (IAN) and lingual nerve (LN) injury, to examine possible contributing risk factors and to describe the pattern of recovery. 3595 patients were included (61% female, 39% male; age range, 14-82 years). Of the 4338 lower third molar extractions performed by various grades of operators, 0.35% developed IAN deficit and 0.69% developed LN deficit. Distoangular impaction was found to increase the risk of LN deficit significantly (p<0.001). Depth of impaction was related to the risk of IAN deficit (p<0.001). Undergraduates caused more LN deficits (p<0.001). Sex, age, raising of a lingual flap, protection of LN with a retractor, removal of distolingual cortex, tooth sectioning and difficulty in tooth elevation were not significantly related to IAN or LN injury. Postoperative recovery from IAN and LN deficits was noted most significantly at 3 and 6 months, respectively. By the end of the follow-up period, 67% of IAN deficits and 72% of LN deficits had recovered completely.